import java.util.Random;
import java.util.Scanner;
public class Main {
    public static void main9(String[] args) {
        //给定一个数字，判定其是否是素数
        Scanner scanner = new Scanner(System.in);
        int num = scanner.nextInt();
        int flag = 1;
        for(int i = 2; i < num; i++) {
                if(num%i == 0) {
                    flag = 0;
                    System.out.println("no");
                    break;
                }
            }
        if(flag == 1 && num != 1) {
            System.out.println("yes");
        }
    }
    public static void main8(String[] args) {
        //编写程序数一下 1到 100 的所有整数中出现多少个数字9
        int count = 0;
        for(int i = 1; i < 100; i++) {
            int tmp = i;
            while(tmp!=0) {
                if(tmp%10==9) {
                    count++;
                }
                tmp/=10;
            }
        }
        System.out.println(count);
    }
    public static void main7(String[] args) {
        //写一个函数返回参数二进制中 1 的个数
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int count = 0;
        while(n!=0) {
            if((n&1)== 1) {
                count++;
            }
            n>>>=1;
        }
        System.out.println(count);
    }
    public static void main6(String[] args) {
        //求两个正整数的最大公约数
        Scanner scanner = new Scanner(System.in);
        int a = scanner.nextInt();
        int b = scanner.nextInt();
        int min = a<b?a:b;
        while(min>=1) {
            if(a%min==0 && b%min==0) {
                System.out.println(min);
                break;
            }
            min--;
        }
    }
    public static void main5(String[] args) {
        //输出乘法口诀表
        for(int i = 9; i >= 1; i--) {
            for(int j = 1; j <= 9; j++) {
                if(i<=j) {
                    System.out.printf("%dx%d=%2d  ",i,j,i*j);
                }
            }
            System.out.println();
        }
    }
    public static void main4(String[] args) {
        //输出 1000 - 2000 之间所有的闰年
        for(int year = 1000; year <= 2000; year+=2) {
            if(year%400==0 || year%4==0 && year%100!=0) {
                System.out.println(year);
            }
        }
    }
    public static void main3(String[] args) {
        //打印 1 - 100 之间所有的素数
        int i = 0;
        for(i = 2; i < 100; i++) {
            int flag = 1;
            for(int j = 2; j < i; j++) {
                if(i%j==0) {
                    flag = 0;
                }
            }
            if(flag == 1) {
                System.out.println(i);
            }
        }
    }
    public static void main(String[] args) {
        //根据年龄, 来打印出当前年龄的人是少年(低于18), 青年(19-28), 中年(29-55), 老年(56以上)
        Scanner scanner = new Scanner(System.in);
        int age = scanner.nextInt();
        if(age<=18) {
            System.out.println("少年");
        } else if(age>=19 && age<=28) {
            System.out.println("青年");
        } else if(age>=29 && age<=55) {
            System.out.println("中年");
        } else {
            System.out.println("老年");
        }
    }
    public static void main1(String[] args) {
        //猜数字游戏
        Random random = new Random();//默认随机种子是系统时间
        Scanner scanner = new Scanner(System.in);
        int toGuess = random.nextInt(100)+1;//1~100
        int count = 8;
        while(count>0) {
            System.out.println("请输入您要猜的数字");
            int num = scanner.nextInt();
            if(num<toGuess) {
                System.out.println("猜小了");
            } else if(num==toGuess) {
                System.out.println("猜中了");
                break;
            } else {
                System.out.println("猜大了");
            }
            count--;
        }
    }
}